The World Cup is taking shape - and I am happy to say the Brazil team is too. It looks like Carlo Ancelotti has found his best XI and we have improved and gained momentum and confidence with each game of the group stage. We are getting better at the right time and we have to be, because Japan will be a big challenge in the last 32.

It feels like we are on track, and a big part of that is down to Matheus Cunha. He is the key to a lot of what we are doing so well. It is quite funny to be saying this because usually the Brazil public expects a classic number nine to be leading our attack, and Cunha is different from what the fans are normally looking for. He is more of a nine-and-a-half. Someone who can play like a nine, but also a 10 to link play and create for others. So he is not like Ronaldo, Adriano or Romario, some of our great strikers of the past 30 years, but because he can also score goals - he has three so far at this tournament - he is not a playmaker, either. Instead, he gives the team something that Brazil have maybe never had before, in terms of a centre-forward anyway.

This video can not be played Cunha scores twice as Brazil beat Haiti

In some ways, Cunha reminds me a lot of my old Liverpool team-mate Roberto Firmino in the way he is always dropping deep, and giving the defender marking him a doubt about what to do. If the defender follows him, it gives more space and freedom to Vinicius Jr and Rayan. If the defender leaves Cunha, then he has time to play between the lines, get on the ball and look for passes or shoot. Cunha seems very happy and comfortable with his role, including the defensive side of it when he starts the press or plays almost like a number six in front of the midfield, and it seems to be working for the team in terms of the balance it gives to our attack.

Here, Cunha (highlighted by the star) is deep in his own half to help break up a Scotland attack and has just collected the ball from Brazil's right-back Danilo... Cunha (highlighted playing the pass, centre) then has space to burst forward to start an attack, carrying the ball into the Scotland half, and with Vinicius Jr and Rayan staying high up the pitch in front of him, he has runners to feed and send through on goal.

It was very strange for Brazil to be going into a World Cup without knowing who our best number nine was. Even until the Scotland game, no-one knew who the first choice centre-forward would be. I don't think Ancelotti knew before the tournament either, because he tried Cunha, Igor Thiago, Endrick, Joao Pedro and Richarlison. Sometimes, though, injuries help a manager make decisions. You can almost stumble on to a combination that works well and this time maybe one has helped Brazil.

Raphinha is an amazing player but he likes to move around a lot. In the first game, against Morocco, he played as 10 behind Thiago, and he can also play on either wing. But, when he injured his hamstring against Morocco, he was replaced by Rayan, who is more of a player who will stay on the right. So, having Vini on one side and Rayan on the other gives even more space for Cunha in the areas he likes. He is on his own there a lot, and with his style of play, that suits him.

Things can still change, of course. Thiago gives us something different, maybe if we are chasing the game or playing someone with more physicality. He can stay high up, fix himself on the centre-halves, and occupy that space. The important thing is that Ancelotti has options now and it will be interesting to see what he does next. Back home, though, more and more people are thinking Cunha is the answer and I just hope he continues like this.

Yes, other teams will know about him now, and what he does - but he is such a clever player, he will still not be easy to stop. Cunha's touch map against Scotland shows 15 of his 38 touches (39%) were in his own half, a similar story to when he started their second game against Haiti and 14/41 (34%) were in his own half or the centre circle.

Everything I have talked about so far is down to the manager. The best thing about Ancelotti is that he is so adaptable. He has worked in so many leagues with so many clubs and different players and always won. Everyone talks about his man-management and how he gets the best out of people that way, but I think sometimes they forget that he is very good tactically too.

One of the things I have noticed about Ancelotti's Brazil is that they are not worried about giving the ball to their opponent. We are not a team that needs to have 70% possession all the time. This video can not be played Scotland hopes on the brink following defeat against Brazil Sometimes, if you give the ball to the other team it becomes a problem for them. And, if you get in the right position and press at the right moment, and with the right intensity, you can punish them. That worked against Scotland, with the first goal and the second one which was - harshly - disallowed too, and it was not down to luck. We scored similar goals before the World Cup, in warm-up games against Panama and Egypt as well.

Against Scotland we gave them the ball and we were sending their players where we wanted them to be. We did not have the ball but we had control and then, at the right time, we pressed. It was part of Ancelotti's plan to set a trap, and it worked. Everyone is obsessed with the identity of a team - for example, are you a possession side and always attacking, or defensive and looking for breakaways? With Ancelotti, it is down to the opposition or the moment in the game. If you have got individuals who can adapt like we have, then why not adapt as a team?

This is a new Brazil and I think we need to be different from our teams of the past. By that I don't mean we are sending people back, defending deep and not scoring, but this is the first World Cup where we don't have our full-backs really offensive and flying forward; you know, the way we usually see from Roberto Carlos, Cafu, Maicon, Marcelo or Dani Alves - the list goes on!

Instead, with Douglas Santos and Roger Ibanez or Danilo, they are more conservative with their runs, but that is another reason Vini can stay higher up the pitch and be fresher when we attack. The back four looks really solid and the right balance is now there in midfield too.

In the first game against Morocco, Casemiro was left very exposed on his own in the middle. He was criticised a lot by people afterwards but it was not his fault - it has never been his game to try to be everywhere making tackles and presses, and it definitely is not now he is 34. Since then, however, we have moved from a 4-2-3-1 formation to a 4-3-3. So, if Bruno Guimaraes goes forward the way we want him to, Casemiro still has Lucas Paqueta alongside him. It means we have controlled that situation better against Haiti and Scotland and it will be especially important against Japan, who are a much more fluid and dangerous attacking side than both of those teams.

So, there are lots of reasons to be positive - in defence, where we have only conceded one goal so far, and also in attack where we have scored seven - but in the end all that matters is that we keep on winning. That is what makes the Brazil public smile with the team and, at the moment, they are smiling. Before the first game there was anxiety and, afterwards, everyone was really worried. After three games, though, everyone is really excited.

Lucas Leiva was speaking to BBC Sport's Chris Bevan.

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